repmgr+pg12构建高可用集群（2）

为了使repmgr正常运行，需要对postgresql.conf进行配置

 

#  监听所有网段，默认为 localhost ，只监听本地的连接
listen_addresses = '*'
#  数据库监听端口设置为 5432
port = 5432
#  最大的流复制连接数，一般为备数据库连接数量，同时 pg_basebackup 需要通过流复制连接进行备份
max_wal_senders = 32
#  最多使用的复制槽数量
max_replication_slots = 32
#  最少保留的 WAL 日志数量
wal_keep_segments = 512
# WAL 日志级别，级别越高记录的日志越多，数据库至少配置为 replica，PostgreSQL 9.5和更早版本为hot_standby或者logical
wal_level = 'replica'  或 'logical'
#  开启热备模式，备数据库接受读连接
hot_standby = on
#  备数据库查询事务反馈给主数据库，防止因为数据变化导致查询中断，repmgr需要能够连接到它管理的每台服务器。
hot_standby_feedback = on
#  开启归档
archive_mode = on
#  归档命令，将 WAL 日志拷贝到归档目录 xxxx/archive 下
archive_command = 'test ! -f xxxx/archive/%f && cp %p xxxx/archive/%f'
#  数据页变动时，将整个数据页写入 WAL 日志，执行 sys_rewind 时需要
full_page_writes = on
#  执行 sys_rewind 时需要
wal_log_hints = on
#  开启数据库日志收集
logging_collector = on
#  日志格式为 csv 格式
log_destination = 'csvlog'
#  日志文件存储路径为数据目录下的 log 目录
log_directory = 'log'
#  预加载 lib 库文件，需要将 repmgr 库写入此变量，可以写多个库文件，以 ',' 进行分隔
shared_preload_libraries = 'repmgr'

 

举例

1、数据库配置

listen_addresses = '*'
port = 5432
max_wal_senders = 32
max_replication_slots = 32
wal_keep_segments = 512
wal_level = 'replica'
hot_standby = on
hot_standby_feedback = on
archive_mode = on
archive_command = 'test ! -f /var/lib/pgsql/12/archive/%f && cp %p /var/lib/pgsql/12/archive/%f'
full_page_writes = on
wal_log_hints = on
logging_collector = on
log_destination = 'csvlog'
log_directory = 'log'
shared_preload_libraries = 'repmgr'

----------------

  pg_hba.conf

host    replication     all             0.0.0.0/0                 trus

2、主机repmgr.conf

node_id=1                        
node_name='node1'                        
conninfo='host=192.168.101.9 port=5432 user=postgres  dbname=postgres'                 
data_directory='/var/lib/pgsql/12/data'    

3、查询主机状态

[postgres@localhost bin]$ ./repmgr cluster show
 ID | Name  | Role    | Status    | Upstream | Location | Priority | Timeline | Connection string
----+-------+---------+-----------+----------+----------+----------+----------+-------------------------------------------------------------
 1  | node1 | primary | * running |          | default  | 100      | 1        | host=192.168.101.9 port=5432 user=postgres  dbname=postgres

4、备机repmgr.conf

node_id=2                      
node_name='node2'                                                        
conninfo='host=192.168.101.7 port=5432 user=postgres  dbname=postgres'                                               
data_directory='/home/postgres/pgsql/12/data''

5、克隆备机，调用的pg_basebackup进行备机创建

[postgres@localhost bin]$ ./repmgr standby clone -h 192.168.101.9 -Upostgres
NOTICE: destination directory "/home/postgres/pgsql/12/data" provided
INFO: connecting to source node
DETAIL: connection string is: host=192.168.101.9 user=postgres
DETAIL: current installation size is 24 MB
NOTICE: checking for available walsenders on the source node (2 required)
NOTICE: checking replication connections can be made to the source server (2 required)
INFO: creating directory "/home/postgres/pgsql/12/data"...
NOTICE: starting backup (using pg_basebackup)...
HINT: this may take some time; consider using the -c/--fast-checkpoint option
INFO: executing:
  /usr/pgsql-12/bin/pg_basebackup -l "repmgr base backup"  -D /home/postgres/pgsql/12/data -h 192.168.101.9 -p 5432 -U postgres -X stream
NOTICE: standby clone (using pg_basebackup) complete
NOTICE: you can now start your PostgreSQL server
HINT: for example: pg_ctl -D /home/postgres/pgsql/12/data start
HINT: after starting the server, you need to register this standby with "repmgr standby register"

6、启动并注册备机

#启动
./pg_ctl -D /home/postgres/pgsql/12/data start
#注册
[postgres@localhost bin]$ ./repmgr standby register
INFO: connecting to local node "node2" (ID: 2)
INFO: connecting to primary database
WARNING: --upstream-node-id not supplied, assuming upstream node is primary (node ID 1)
INFO: standby registration complete
NOTICE: standby node "node2" (ID: 2) successfully registered

7、集群状态检查